As the successor to the legendary Patek Philippe reference 1518, the world's first perpetual calendar wristwatch with chronograph function, the reference 2499 was introduced to the market in 1950. The reference 2499 perfectly embodies Patek Philippe's technological and artistic know-how, and has greatly inspired and influenced the configurations of many important wristwatches, needless to mention its successors the reference 3970 and 5970. Over a period of 35 years, reference 2499 was made in the fourth series in a total production of only 349 pieces.